Carnivorous Journey

My pot of D. regia enjoying the sun outside. These plants have more than doubled in size since they were purchased.

To the novice grower scrolling through endless photo threads in hopes of improving their species identification abilities (you know we've all been there), there is little more eye-catching than a well-grown pot of mature D. regia - its common moniker "the King Sundew" is certainly warranted! I too fell into this trap and began to want this species soon after I started growing. However, relatively high online prices and nightmare stories of plants that had died overnight caused me to hold off. Due to a great deal at the NECPS show, I acquired a pot of several small plants and hoped for the best (pictured on the left, now much larger).

I think that lots of people find D. regia to be so frustrating because they try to grow it like their other Drosera. In reality, Drosera regia is only distantly related to other sundews (some people actually believe that it should be separated into its own genus entirely) and has cultivation requirements that closely resemble those of Heliamphora and Highland Nepenthes. Under the correct conditions, this species has actually been very hardy and tolerant for me. Still, being that plants online can sell for close to $40, I wouldn't recommend this species to someone that hasn't grown a decent amount of Drosera already.

The most foremost difference between D. regia and other sundews is its appreciation for soil fertilization. While soil fertilization isn't necessary, this species has a huge appetite and I've found it much more visually appealing to fertilize through the roots rather than constantly having every single leaf curled up with prey. I use diluted 25% urea-free orchid fertilizer and the plants seem to enjoy it (this is the same concoction that I use on all of my other CPs that like to be fertilized). I definitely wouldn't suggest placing this species in the same tray as other Drosera, since fertilizer leakage will probably lead to dead plants and lots of tears (it's okay, I'm sure you'll find a new D. capensis).

I keep my D. regia in my HL terrarium, where temperatures never really get above the upper 70s. Given the origin of this species (fairly high elevations in South Africa), I wouldn't suggest letting temperatures get too high. My nighttime temperatures drop down to the low 60s, which the plants definitely seem to enjoy.

I'd imagine that a big drop at night, as well as keeping the roots cool, can help offset daytime conditions that are a tad too hot. Other growers have reported that excessively cold temperatures can trigger dormancy, but, since dormancy isn't required, I maintain the same temperature conditions year-round (which probably isn't very feasible if you grow them in a greenhouse in a temperate climate).

I've kept my plants in both the most humid (70%+) and the least humid (around 40%) parts of the terrarium. To be quite honest, they didn't really seem to have a discernible preference. So long as other conditions are favorable, it doesn't seem to me as though humidity is overall a major factor in cultivation success.

Leaf closeup. Lots of dew!

Like Heliamphora, this species appreciates a well-draining, airy medium. Anything with a decent amount of perlite or sand should be fine. In addition, live sphagnum can be used as a top dressing to help keep root temperatures low. I water these plants like all of my other Drosera (moist, not excessively wet), and have never had any problems. I've heard of some growers having issues with rot, but I expect that it's completely avoidable if the plants aren't over-watered.

Light is pretty self-explanatory. Like pretty much most CPs (with the exception of D. schizandra and maybe a few others), bright light is pretty much a requirement. I keep my plants under T5HOs year-round. This isn't really a species that'll color up too much; even growers that keep their plants under strong, direct natural sunlight may only get significant reddish hues in the tentacles or at the bases of the leaves.

The overall takeaway from this should be that, given the right conditions (bright light, cool temperatures, airy media), D. regia can actually be a fairly fast-growing and tolerant species. In my opinion, it's definitely one of the best species out there, and anybody contemplating whether or not they should cultivate it should bite the bullet and give it a try - you won't regret it! I'll now pass the mic over to Alvin, who's going to speak about his experiences propagating D. regia.

​- Dan ​

​Despite the relatively high prices it commands in the market, D. regia is actually quite easy to propagate. The two methods used most often (aside from those with access to tissue culture equipment) are by seed and root cuttings.

D. regia seed is quite unlike other Drosera seed in that it does not require a magnifying glass in order to view in detail - they are, in fact, quite large! This also means that funny mistakes like dropping an open seed packet will be less likely to make you curse in frustration as with other Drosera seed (not that I've ever done anything like spill packets of seed all over myself, that would be silly!). Sow seeds on the surface of medium that you would grow adult plants in and give them the same conditions that a growing plant would expect. They germinate usually within 2-4 weeks, often quicker than many subtropical Drosera. No stratification or special treatment to induce germination is necessary. After the seedlings have developed a number of true leaves they will need to be heavily and constantly fed.

These young D. regia were started from seed and are about 10 months old now. They are growing in 100% LFS with a live Sphagnum top dressing. The top dressing is not necessary but I like how it looks.

D. regia seed, 40X. These things are enormous compared to other Drosera seeds!

D. regia has exceptionally handsome mucous globules in my opinion.

I apply crushed beta fish food pellets to the leaves and fertilize the plants via the roots with the same concentration of orchid fertilizer I use on Nepenthes and Heliamphora. Other growers prefer Osmocote or satisfy their ghoulish desires by supplying the plants with live insects and

watching the leaves dramatically curl over the hapless creature over the course of several hours. It does not matter as long as the plants are getting a suitable amount of nutrients. Some growers report that this species is difficult from seed since their seedlings tend to die after they have developed a number of true leaves. I think that this is likely a result of the seedlings starving to death as I have never had this problem. ​​

Small plantlet from a root cutting

D. regia has thick, fleshy roots that are ideal for root cuttings. If you are ever in a situation where the roots of a healthy plant are exposed (i.e. repotting) and you have the opportunity and desire to lop off a few, taking a few cuttings is an excellent way to get a number of large plants quickly. When I propagated this species from root cuttings in the past I chopped the roots into segments about 1'' long , laid them on the surface of some moist Sphagnum, and covered them with a few sprigs of Sphagnum (enough to keep the cuttings hydrated but still allow light to penetrate through to them). Plantlets started developing from the roots after around 2 weeks for me. Plants from root cuttings will attain a larger size more quickly than plants from seed.

Additionally, if you have a larger plant that is declining in health for some reason, root cuttings may be used as a final resort to propagate it before it croaks as long as there are still healthy roots.

Dan said that they do not color up much in bright light, but I had one in my PNW bog for a few years growing in full sun and its tentacles were much redder than those grown under artificial lighting or filtered sunlight. The leaves were much narrower and the overall size of the plant was smaller, I assume due to not requiring tall wide leaves because it was getting lots of sunlight? I have a photo but can't add it here. The one grown in my garage south-facing window with T12 lights above it got huge tall wide leaves that were the typical green color, looked more like a typical regia you see in photos.

Reply

Alvin

4/16/2017 08:13:34 pm

Hey Djoni, great to see you here! I haven't been as active on the forums lately so I've been missing a lot of what's been going on, I hope you and the plants are well!

Another grower right before you pointed out that his D. regia tend to develop a reddish hue near the leaf bases when grown under strong direct light and the article has been edited to reflect that - Dan originally meant that the laminas of this species do not fully color up like in most other subtropical species and usually stay greenish. I haven't heard too much about how strong sunlight affects tentacle coloration or plant size, but now looking at some photos of the plants in situ I definitely see some significant tentacle coloration although the plants still seem to be pretty large. Perhaps there is some slight variation between different D. regia clones? Although Dan and I have a number of different clones we can't grow them outside long-term here in NJ so we don't know how they'd look under direct sun. Any chance you know where yours originated, and if the plants you have outdoors and indoors are the same clone? It does make a lot of sense that a plant outdoors would have redder tentacles and an overall smaller size, although I do wonder why the laminas themselves don't color up, another significant difference between D. regia and most other 'dews. If you'd like to email us your photo of your outdoors plant or post on the forums to continue the discussion please do so, I'm very interested in hearing about your observations of growing this plant outdoors in the PNW!

I have a young Drosera regia which I purchased in Autumn of 2016. I placed it in my glass porch which acts as a greenhouse for my plants. The plant stands in approximately 1 inch of water with about 3 inches of the pot clear of the water (tray method). It was partly dormant when purchased but here in Wales, UK, winters aren't harsh and the plant actually continued to produce leaves with dew during the winter. Consequently I fed the leaves with dried blood worm. During the spring this year the plant took off and the leaves were 6 - 8 inches in length and catching there own small flies supplemented by me with dried blood worm. Every three weeks or so the leaves started to die off from the top to the base; they started turning yellow and then black at the tip but the rest of the leaf remained dewy and would catch flies. I have assumed that as with other carnivorous plants this occurred because the leaf had lived out its useful life and in each case the surface of these leaves where covered in insects. During this month (July) as well as the leaf die off described the new leaves being produced are not opening up into a flat leaf surface covered with tentacles with dew but remaining partly flattened in a V or U shape with much less dew evident. They are also slightly shorter. The plant has been exposed to some very sunny days and overcast ones but in the main it gets bright light and sunshine most days. Temperatures can get up to high 80sF but usually it is less and with a drop to the 60sF at night. I went on holiday for one week at the end of June and the plant was moved indoors in case it dried out. During this time it was in a shady location. It was returned to the porch at the end of the week. Although that move coincides with the symptoms I am describing is it too obvious to be the cause? Could you please suggest any other possible reason for the plant behaving this way, and what do I do about it? Thank you.

From what you described, I cannot tell definitely any reason for your plant's sudden decline other than the week it spent indoors in a shady location, since your conditions largely seem to keep the plant happy otherwise and you are regularly feeding it. I have noticed that D. regia does not appreciate sudden changes in growing conditions, and that after being moved it tends to sulk for a while before recovering. If the humidity indoors is much lower than outside that could also exacerbate the issue of the sudden decrease in light and air movement, which would very likely lead to the weaker growth and loss of dew that you observed. In low-light conditions D. regia may also be susceptible to rot (especially in heavier peat-based soil mixes), but if the crown of your plant appears healthy I doubt this is an issue. Now that your plant has been returned to its normal growing area I believe it should recover, but I would monitor it carefully over the next several weeks for any further signs of decline. Good luck!

Do you have any insights for things to try if trying to grow Drosera Regia in a warmer climate? Short of moving, that is. We don't get major temperature drops in the summers and the daytime temperatures can be in the low to mid 30s and nights around 28 to 31 degrees. Humidity should not be an issue.

Reply

Alvin

9/21/2017 08:11:18 pm

Hi Vidyut, unfortunately neither of us have experience growing D. regia in warmer climates. My recommendation would be to try to set up some sort of growing enclosure or area where you can drop the temperature at night. I think D. regia should be able to grow well in intermediate temperatures and take elevated daytime temperatures with nighttime cooling, but consistent temperatures around 30C would definitely be pushing it.